Target sighting systems

ABSTRACT

A target sighting system, principally for a fighting vehicle having a main armament which can be aimed by a gunner by means of a sighting periscope rotatable in azimuth, is provided with a separate periscope, principally for a vehicle commander, which can be independently rotated in azimuth, and optical passageways in each periscope system which provide a direct optical path between the periscopes when they are aligned in azimuth so that the view through the gunner&#39;&#39;s periscope can be observed through the other periscope.

waited States Fatemt 1 Kellow Feb. 5, 1974 TARGET SIGHTING SYSTEMS 3,326,619 6/1967 Johnson et a1 350/16 [76] Inventor: Allan Neville Kellow, 124,

Selbourne Ave., New Haw, Weybridge, Surrey, England Filed: Sept. 7, 1971 Appl. No.: 178,204

US. Cl 350/10, 350/34, 350/52, 356/251 Int. Cl. G02b 27/32, G02b 23/08 Field of Search... 350/10, 301, 34, 52, 302, 16; 356/250, 251

References Cited UNITED STATES PATENTS Scidmore Spring 350/52 X Primary Examiner-David H. Rubin Attorney, Agent, or FirmCamer0n, Kerkam, Sutton, Stowell & Stowell 571 ABSTRACT A target sighting system, principally for a fighting vehicle having a main armament which can be aimed by a gunner by means of a sighting periscope rotatable in azimuth, is provided with a separate periscope, principally for a vehicle commander, which can be independently rotated in azimuth, and optical passageways in each periscope system which provide a direct optical path between the periscopes when they are aligned in azimuth so that the view through the gunners periscope can be observed through the other periscope.

9 Claims, 1 Drawing Figure TARGET SIGHTING SYSTEM The invention relates to target sighting systems principally, but not exclusively, for fighting vehicles.

In a fighting vehicle with a stabilised armament which is automatically maintained on target, and from which a gunner can make observations via a periscope, it is known to link the sighting mirror of the periscope to the stabilised armament so that the gunners line of sight through the periscope may also be automatically maintained on target.

In a fighting vehicle such as a tank, having a commander as well as a gunner, the commander is normally provided with a separate periscope. The invention provides an improved target sighting system which enables the vehicle commander to rotate his periscopic line of sight as far as desired in azimuth, to set accurately on target any weapon, if provided, under his control, and also to observe the aiming point of and even fire the main armament while the vehicle is moving. In addition, a magnified view of the target may be readily provided for the commander.

Although the invention is primarily applicable to fighting vehicles whether land, water or airborne, equipped with guns or like armaments, it is also applicable to any vehicle or even a stationary unit, equipped with a directable device such as a camera or other optical or scientific instrument. The target may similarly be any point or object which it is desired to identify, observe'or fix its location.

According to the invention, a target sighting system comprises a first and a second sighting periscope each rotatable in azimuth relative to the other, the second periscope having a graticule in its sighting system which indicates the direction of a directable device, such as the stabilised main armament of a fighting vehicle, each periscope having an optical pathway in fixed relation to its azimuth arranged so that when the two periscopes are aligned in azimuth a direct optical path is provided between the periscopes whereby an observer viewing through the first periscope can observe the view through the second periscope and a superimposed image of its graticule.

Usually the second sighting periscope is provided with a sighting mirror aligned with the azimuth and linked to the elevation of the said directable device,

Preferably the first sighting periscope has a first viewing position, for example a viewing screen, at which the view from the periscope can be observed in the usual way, but is provided with a magnifying optical system having a second viewing position, normally an eyepiece, and conveniently close to the first viewing position, at which a magnified view can be observed, and a mirror device provided with first or lower and second or upper reflecting faces and which can be placed in a first position at which it is excluded from the optical system of the first periscope and which can be placed in a second position at which it can reflect from its second or upper face light rays from the first periscope to the first viewing position of the first periscope, and, when the two periscopes are aligned in azimuth, simultaneously reflect from its first or lower face light rays from the second periscope through the magnifying optical system to provide a magnified view of the target at the second viewing position.

Preferably, when the mirror is in its first position the light rays from the first periscope are arranged to pass through the magnifying optical system to provide a magnified view from the first periscope.

The first sighting periscope may readily be provided with a sighting mirror which can be moved so as to change the elevation of the view of the first periscope. The sighting mirror may also be aligned with the azimuth and linked to the elevation of a further directable device, for example, a light gun such as a machine gun. Both or either sighting periscope may be binocular.

The invention will now be described by way of example only and with reference to the accompanying drawing which is a diagrammatic vertical cross-sectional view of a target sighting system for a fighting vehicle with its first and second sighting periscopes aligned in azimuth.

In the FIGURE, the sighting mirror I of a first sighting periscope is pivoted about a horizontal axis 2 the rotation of which is controlled through a 21 drive,

represented schematically by 3, connected to a machine gun (not shown) mounted on the rotatable cupola 4 of a fighting vehicle. Cupola 4 also carries the sighting mirror 1, and the machine gun and sighting mirror 1 are aligned in azimuth. A mirror device 5 is pivoted about a horizontal axis 6 and is capable of being arranged in two stable positions as shown by the full and dotted lines. When the mirror device 5 is in the angled position shown by the full lines, light reflected towards the mirror device 5 from mirror 1 is reflected by the second or upper surface 5a to a viewing window 7. When the mirror device 5 is in the vertical position shown by the dotted lines, light reflected from mirror 1 passes through a magnifying optical system comprising a lens combination 8, internally reflecting prisms 9 and 10 and an eyepiece lens ll. The focal lengths of the lenses 8 and 11 and their relative position are arranged so that a magnified image is seen through eyepiece lens ll. The mirror 1, mirror device 5, lenses 8, l1 and prisms 9, 10 are all carried by the cupola 4 which rotates with respect to the supporting ring 12 of the cupola. Reference 13 indicates a bearing between the cupola 4 and supporting ring 12. A second sighting periscope comprises a sighting mirror 14 pivoted at 15 about a horizontal axis the rotation of which is controlled through a 2-1 drive, represented schematically by 16, connected to a stabilised main armament (not shown). Sighting mirror 14 is aligned in azimuth with the stablised main armament and is carried by the supporting ring 12. Light reflected from sighting mirror 14 is internally reflected by a prism 17 which is also carried by the supporting ring 12, passes through passages 19, 18 machined in the supporting ring 12 and the cupola 4 respectively towards the first or lower surface or face 5b of mirror device 5. When the mirror device 5 is in the angled position the light is then reflected through the lens 8, the prisms 9 and 10 and the eyepiece lens U. The graticule 20 is illuminated by a light source 211, and an image of the gratciule 20 is made visible at the eyepiece 11 via the lens system 22 in the collimator 23, the prism 17, passages 18 and 19, by reflection at mirror device 5 and passage through prisms 9 and It).

In operation, in an armoured fighting vehicle such as a tank, the cupola 4 is rotatable throgh 360 about a vertical axis, and with mirror device 5 in the angled position, the commander watching through the window 7 and rotating with the cupola may make observations all round the vehicle at a magnification of X1, with the line of sight of the first periscope parallel to the direction in which the machine gun mounted on the cupola is pointing. If the angle of elevation of the machine gun is altered, the sighting mirror 1 is rotated by means of the 2-1 drive 3 so that the line of sight remains substan tially parallel to the machine gun. If a graticule (not shown) is included in the sighting system it may be used to assist the aiming of the machine gun. If the mirror device 5 is then moved to the vertical position by lever means (not shown), a magnified view is obtained through the eyepiece l1 and the movement of the commanders head from the viewing window 7 to the eyepiece 11 is small.

If the cupola 4 is moved to a position such that passages 18, 19 are substantially aligned in azimuth and the mirror device 5 is in the angled position, a magnified view along the line of sight from sighting mirror 14 will be obtained through eyepiece lens 11. Since the sighting mirror 14 is aligned in azimuth with the main armament which is normally under the control of a gunner viewing through a gunners periscope (not shown, and since an alteration in elevation of the main armament imparts through the 2-11 drive 16 a movement to the sighting mirror 14 such that the line of sight through the sighting mirror 14 and the direction of the main armament are substantially parallel, the system may be used by the commander to monitor the aim of the main armament, the point of superimposition of the second gun on the target being indicated by the image of graticule 20 at eyepiece 11.

Since the main armament (and therefore the sighting mirror 14) is stabilised, the commander need not move his head to keep the target in view and consequently can monitor the gunners aim continuously, and the main armament can be fired by the commander even when the tank is moving over rough ground.

A suitable magnification provided by the magnifying optical system comprising the lenses 8, ll ranges from X8 to X20, for example X10, X12 or X15.

1 claim:

1. A target sighting system comprising a first and a second sighting periscope, means so connecting said periscopes that each is rotatable in azimuth relative to the other, a directable device fixed in azimuth in relation to the second periscope, a graticule in the sighting system of the second periscope which graticule indicates the direction of the directable device, each periscope having an optical pathway in fixed relation to its azimuth, which pathways are aligned when the first and second periscopes are aligned in azimuth, whereby a direct optical path is then provided between the periscopes, and an observer viewing through the first periscope can observe the view through the second periscope and a superimposed image of its graticule.

2. A target sighting system according to claim 1 wherein the directable device is the stabilised main armament of a fighting vehicle.

3. A target sighting system according to claim 1 wherein the second periscope has a sighting mirror, means coupling said sighting mirror to said directable device in alignment with the azimuth of said device, and means linking said sighting mirror with the elevation of said directable device. *7

4. A target sighting system according to claim 3 wherein the first sighting periscope has a first viewing position at which the view from the periscope can be observed, a magnifying optical system having a second viewing position at which a magnified view can be observed; and a mirror device provided with lower and upper reflecting faces at which can be placed in a first position at which it is excluded from the optical system of the first periscope and which can be placed in a second position at which it can reflect from its upper face light rays from the first periscope to the first viewing position of the first periscope, and, when the two periscopes are aligned in azimuth, simultaneously reflect from its lower face rays from the second periscope through the magnifying optical system to provide a magnified view of the target at the second viewing position.

5. A target sighting system according to claim 4 wherein when the mirror device is in its first position, light rays from the first periscope are arranged to pass through the magnifying optical system.

6. A target sighting system according to claim 4 in which said magnifying optical system is a lens system prq idins taasa fi ti nin th ran c r m X8 to 0- 7. A target sighting system according to claim 1 wherein the first sighting periscope has a sighting mirror which can be moved so as to change the elevation of the view of the first periscope.

8. A target sighting system according to claim 7 including a further directable device, means coupling the sighting mirror of the first periscope to said further directable device in alignment with the azimuth of said further directable device, and means linking said sighting mirror with the elevation of said further directable device.

9. A target sighting system according to claim 8 wherein the said further directable device is a light gun. =l= 6 i =F UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent NO. Dated Inventor-( Allan Neville Kellow It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Cover page, after item [761 insert --[73] Assignee& The Secretary of State for Defence in Her Britannic Majesty's Government of the United Kingdom of Great Britain and Northern Ireland, London, England--. Column 4, line 26, after "face" insert -light-.

Signed and sealedthis 20th day of August 197a.

(SEAL) Attest:

McCOY M. GIBSON, JR. I C. MliRSHALL DANN Attesting Officer Commissioner of Patents UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent NO. Dated Inventor-( Allan Neville Kellow It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Cover page, after item [761 insert --[73] Assignee& The Secretary of State for Defence in Her Britannic Majesty's Government of the United Kingdom of Great Britain and Northern Ireland, London, England--. Column 4, line 26, after "face" insert -light-.

Signed and sealedthis 20th day of August 197a.

(SEAL) Attest:

McCOY M. GIBSON, JR. I C. MliRSHALL DANN Attesting Officer Commissioner of Patents UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent: No. 3 790/1248 hated Feb. 5, 1974 Inventor) Allan Neville Kellow It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Cover page, after item [761 insert v v --[73] Assigneei The Secretary of State for Defence in Her Britannia Majesty's Government of the United Kingdom of Great Britain and Northern Ireland, London, England--.

Column 4, line 26, after "face" insert -'--light--.

Signed and sealed this 20th day. of Au ust 197 (SEAL) Attest:

COY M. GIBSON T JR. C. MARSHALL DANN ttesting Officer Commissioner of Patents 

1. A target sighting system comprising a first and a second sighting periscope, means so connecting said periscopes that each is rotatable in azimuth relative to the other, a directable device fixed in azimuth in relation to the second periscope, a graticule in the sighting system of the second periscope which graticule indicates the direction of the directable device, each periscope having an optical pathway in fixed relation to its azimuth, which pathways are aligned when the first and second periscopes are aligned in azimuth, whereby a direct optical path is then provided between the periscopes, and an observer viewing through the first periscope can observe the view through the second periscope and a superimposed image of its graticule.
 2. A target sighting system according to claim 1 wherein the directable device is the stabilised main armament of a fighting vehicle.
 3. A target sighting system according to claim 1 wherein the second periscope has a sighting mirror, means coupling said sighting mirror to said directable device in alignment with the azimuth of said device, and means linking said sighting mirror with the elevation of said directable device.
 4. A target sighting system according to claim 3 wherein the first sighting periscope has a first viewing position at which the view from the periscope can be observed, a magnifying optical system having a second viewing position at which a magnified view can be observed; and a mirror device provided with lower and upper reflecting faces at which can be placed in a first position at which it is excluded from the optical system of the first periscope and which can be placed in a second position at which it can reflect from its upper face light rays from the first periscope to the first viewing position of the first periscope, and, when the two periscopes are aligned in azimuth, simultaneously reflect from its lower face rays From the second periscope through the magnifying optical system to provide a magnified view of the target at the second viewing position.
 5. A target sighting system according to claim 4 wherein when the mirror device is in its first position, light rays from the first periscope are arranged to pass through the magnifying optical system.
 6. A target sighting system according to claim 4 in which said magnifying optical system is a lens system providing a magnification in the range from X8 to X20.
 7. A target sighting system according to claim 1 wherein the first sighting periscope has a sighting mirror which can be moved so as to change the elevation of the view of the first periscope.
 8. A target sighting system according to claim 7 including a further directable device, means coupling the sighting mirror of the first periscope to said further directable device in alignment with the azimuth of said further directable device, and means linking said sighting mirror with the elevation of said further directable device.
 9. A target sighting system according to claim 8 wherein the said further directable device is a light gun. 